Rachel Nowak Vive la difference – between men. That's the attitude of the female painted dragon lizard, which lives across the southern states of Australia. The females are polyandrous, and mate with as many males as possible. That is easy, because they only need to copulate for 10 seconds before males ejaculate. What is more, they store ejaculates inside their reproductive tracts for up to five months, forcing sperm from different males to compete to fertilise their eggs. Evolutionarily speaking, this all makes good sense. By encouraging competition the female increases her chances of getting hold of good-quality sperm. What has been a mystery is the fact that the brightly-coloured male dragons come in more than one version: some have red heads, some yellow heads, and a third version – discovered last year – have orange heads. Usually natural selection weans out inferior versions of an organism, so the fact that all versions of male painted dragons exist in the population has been hard to explain. Now a team of evolutionary ecologists believe that they have solved a major piece of the puzzle. © Copyright Reed Business Information Ltd

Keyword: Sexual Behavior; Evolution
Link ID: 11558 - Posted: 06.24.2010

By MARILYNN MARCHIONE CHICAGO -- Two years ago, scientists had high hopes for new pills that would help people quit smoking, lose weight and maybe kick other tough addictions like alcohol and cocaine. The pills worked in a novel way, by blocking pleasure centers in the brain that provide the feel-good response from smoking or eating. Now it seems the drugs may block pleasure too well, possibly raising the risk of depression and suicide. Margaret Bastian of suburban Rochester, N.Y., was among patients who reported problems with Chantix, a highly touted quit-smoking pill from Pfizer Inc. that has been linked to dozens of reports of suicides and hundreds of suicidal behaviors. "I started to get severely depressed and just going down into that hole ... the one you can't crawl out of," said Bastian, whose doctor took her off Chantix after she swallowed too many sleeping pills and other medicines one night. Side effects also plague two other drugs: _ Rimonabant, an obesity pill sold as Acomplia in Europe, was tied to higher rates of depression and a suicide in a study last month. The maker, Sanofi-Aventis SA, still hopes to win its approval in the United States. _ Taranabant, a similar pill in late-stage testing, led to higher rates of depression and other side effects in a study last month. Its maker, Merck & Co., stopped testing it at middle and high doses. © Copyright 1996-2008 The Washington Post Company

Keyword: Drug Abuse; Depression
Link ID: 11557 - Posted: 06.24.2010

Mind Matters editor Jonah Lehrer chats with Gary F. Marcus, New York University psychologist and head of the Infant Language Learning Center, about how computing, genetic biology and psychology together can help probe the wonders of human language development. JONAH LEHRER: What first made you interested in studying the development of language in children? GARY F. MARCUS: I came to language development through early exposure to computers, back in the late 1970s and early 1980s, when I was in grade school. I was one of those kids who took to programming like a fish takes to water, and very soon wanted to push the limits: What could I get a computer to do? One obvious thing was to try get a computer program to understand language; I pretty quickly figured out just how hard that was—there was no way I was going to get my Commodore 64 to talk—but along the way I developed an abiding interest in human mind and how it managed to solve difficult problems. And to this day I still find it amazing just how good human children are at learning languages. No other creature comes close, and nor does any computer program, even now, 20 years later. How come our memories are so lousy relative to computers, yet our capacities for learning language are so good? That's the kind of question I like. © 1996-2008 Scientific American Inc.

Keyword: Language; Development of the Brain
Link ID: 11556 - Posted: 06.24.2010

Ten-year-old Charles, who has autism, is happy to tell you a story by himself. But when asked to collaborate with another child on a story, he doesn't have much to say. Autism is marked by impairments in communication and social behavior; people with autism may perform repetitive behaviors and prefer an unchanging environment. Autism is a brain disorder that is typically diagnosed in children before the age of three. The effects of autism vary along a spectrum of severity, but it most often impairs both social interaction and the ability to learn in a typical classroom setting. Valeria Nanclares, child psychologist at Advocate Illinois Masonic Medical Center, explains, "The difference between typically developing peers and children with autism has to do with their ability to build and sustain a conversation. Typically developing kids can understand that they need to pick up on the other child's cues, follow the leads of what they just said, so they can build a conversation," she says. To address that deficit, Justine Cassell, director of the Center for Technology & Social Behavior at Northwestern University and her team developed a life-sized virtual pal named Sam. Sam helps autistic kids practice the back-and-forth exchange of conversation – a skill Cassell says is essential for making social connections and learning in the classroom. © ScienCentral, 2000-2008.

Keyword: Autism
Link ID: 11555 - Posted: 06.24.2010

Ewen Callaway Any hedge-fund manager will tell you that money and status go hand in hand. Now brain-scanning studies suggest that the link between profits and power takes place in the striatum – part of the brain involved in sensing rewards. "This provides the biological basis of our everyday experience that personal reputation is felt as reward," says Norihiro Sadato, a neuroscientist at the National Institute for Physiological Sciences in Aichi, Japan, who led one of the studies. Sadato's team scanned the brains of 19 volunteers while they gambled. Volunteers selected one of three cards that flashed onto a computer screen. After making a choice, the subjects learned of their winnings – between 0 and 60 yen (about $0.50) per card. Volunteers also played the game with no winnings, allowing the researches to compare how the brain responded to profit. After the game, the subjects took a personality quiz and introduced themselves in front of a video camera. Sadato's team told the volunteers they would be evaluated by others. In reality, the researchers faked the evaluations. The next day, volunteers returned to the brain scanner. Instead of money, they received praise or scorn. Photos of each volunteer were flashed across a computer screen with personal judgments like "modest," "trustworthy," and "selfish" next to their picture. © Copyright Reed Business Information Ltd.

Keyword: Emotions
Link ID: 11554 - Posted: 06.24.2010

Human imaging studies have for the first time identified brain circuitry associated with social status, according to researchers at the National Institute of Mental Health (NIMH) of the National Institutes of Health. They found that different brain areas are activated when a person moves up or down in a pecking order — or simply views perceived social superiors or inferiors. Circuitry activated by important events responded to a potential change in hierarchical status as much as it did to winning money. "Our position in social hierarchies strongly influences motivation as well as physical and mental health," said NIMH Director Thomas R Insel, M.D. "This first glimpse into how the brain processes that information advances our understanding of an important factor that can impact public health." Caroline Zink, Ph.D., Andreas Meyer-Lindenberg, M.D., Ph.D., and colleagues of the NIMH Genes Cognition and Psychosis Program, report on their functional magnetic resonance imaging (fMRI) study in the journal Neuron. Meyer-Lindenberg is now director of Germany's Central Institute of Mental Health. Prior studies have shown that social status strongly predicts health. Animals chronically stressed by their hierarchical position have high rates of cardiovascular and depression/anxiety-like syndromes. A classic study of British civil servants found that the lower one ranked, the higher the odds for developing cardiovascular disease and dying early. Lower social rank likely compromises health through psychological effects, such as by limiting control over one's life and interactions with others. However, in hierarchies that allow for more upward mobility, those at the top who stand to lose their positions can have higher risk for stress-related illness. Yet little is known about how the human brain translates such factors into health risk.

Keyword: Stress; Neuroimmunology
Link ID: 11553 - Posted: 06.24.2010

A drug widely used to treat cancer may cause brain damage, with the effects lasting for years after the end of treatment, research suggests. The drug, 5-fluorouracil (5-FU), is used, alongside others, to treat cancers of the breast, ovaries, colon, stomach, pancreas and bladder. Tests on mice showed it destroys vital cells in the brain that help to keep nerves functioning properly. The University of Rochester study features in the Journal of Biology. The researchers say their findings could explain some of the neurological side effects associated with chemotherapy - a phenomenon often known as "chemo brain". These include memory loss, poor concentration, and in more extreme cases, seizures, impaired vision and even dementia. Until recently they were often dismissed as the by-products of fatigue, depression and anxiety related both to the diagnosis and treatment of cancer. But many patients show symptoms: a previous study by the Rochester team found more than 80% of breast cancer patients reported some form of mental impairment after chemotherapy. The latest study found 5-FU attacks oligodendrocyte cells in the brain and the precursor stem cells from which they originate. These cells play a crucial role in the central nervous system, producing myelin, the protective sheath that keeps nerve fibres in working order. If myelin is not constantly renewed, communication between nerve cells is damaged. The researchers showed that oligodendrocytes virtually disappeared from the brains of mice six months after the animals were treated with 5-FU. (C)BBC

Keyword: Neurotoxins; Glia
Link ID: 11552 - Posted: 04.23.2008

A fish species, which is all female, has survived for 70,000 years without reproducing sexually, experts believe. Scientists from the University of Edinburgh think the Amazon Molly may be employing special genetic survival "tricks" to avoid becoming extinct. The species, found in Texas and Mexico, interacts with males of other species to trigger its reproduction process. The offspring are clones of their mother and do not inherit any of the male's DNA. Typically, when creatures reproduce asexually, harmful changes creep into their genes over many generations. The species will eventually have problems reproducing and can often fall victim to extinction. Scientists at Edinburgh University have been studying complex mathematical models on a highly powerful computing system to look at the case of the Amazon Molly. Researchers calculated the time to extinction for the fish based on modelling genetic changes over many thousands of generations. They are now able to say conclusively, for the first time, the fish ought to have become extinct within the past 70,000 years, based on the current simple models. Scientists believe the fish, which are still thriving in rivers in south-east Texas and north-east Mexico, are using special genetic survival "tricks" to help them stay alive. One theory is that the fish may occasionally be taking some of the DNA from the males that trigger reproduction, in order to refresh their gene pool. Dr Laurence Loewe, of the university's School of Biological Sciences, said: "What we have shown now is that this fish really has something special going on and that some special tricks exist to help this fish survive. "Maybe there is still occasional sex with strangers that keeps the species alive. Future research may give us some answers." (C)BBC

Keyword: Sexual Behavior; Evolution
Link ID: 11551 - Posted: 04.23.2008

A person's employment status, gender and marital status all play a part in how much sleep they get, according to new research from Statistics Canada released Tuesday. Canadians who commute, work longer hours and have more kids get less sleep than the rest of the population — affecting the way they live, according to the report. "When we don't get enough sleep, our productivity and behaviour are affected," reads the report. "This impacts the quality of work we do and the quality of our family and personal life at home." The report, which is published in the Spring 2008 edition of Canadian Social Trends, finds that a higher salary equals less sleep, with people who make $60,000 or more a year sleeping 40 minutes less than those who make $20,000, according to 2005 data. People with high incomes also are more likely to have busy lifestyles, spending less time with their kids and participating less frequently in leisurely pastimes. As a result, their lifestyle is more stressful and results in a poorer quality of sleep. People who work full time get less sleep than those who work part time, sleeping 24 minutes less per night. © CBC 2008

Keyword: Sleep
Link ID: 11550 - Posted: 06.24.2010

Eric Bland -- People who spend hours and hours playing video games exhibit the same personality traits as people with Asperger's syndrome, a form of autism. The new research fuels concerns that video games could further alienate an already isolated group of people and increase mental health problems like depression. In the study, John Charlton of the University of Bolton in England and colleagues examined nearly 400 gamers, most of whom were male, and questioned them about how much they played video games. The researchers didn't specifically study people with Asperger's syndrome. The more time a person spent playing video games, the researchers found, the more likely they were to show three specific traits usually associated with Asperger's syndrome: neuroticism and a lack of extraversion and agreeableness. Charlton suggests that people with Asperger's may be more vulnerable to becoming addicted to playing video games because it allows them to escape into a world where they can avoid face-to-face interactions. © 2008 Discovery Communications, LLC

Keyword: Autism; Attention
Link ID: 11549 - Posted: 06.24.2010

By KAREN BARROW Few people over the age of 10 would list “Happy Birthday” among their favorite songs. But Harvey Alter, now 62, has a special fondness for it. It helped teach him how to talk. One morning in June 2003, Mr. Alter, then a self-employed criminologist, was putting a leash on his dog, Sam, in preparation for a walk around Greenwich Village, where he has lived for 30 years. Suddenly he felt dizzy and disoriented. “My thoughts were intertwined, not making sense,” he said in a recent interview. “I knew I was having a stroke.” At St. Vincent’s Hospital, doctors diagnosed an ischemic stroke, caused by a blockage in blood flow to part of the left half of his brain. As a result, the right side of his body was temporarily paralyzed, the right side of his face drooped, and he had trouble coming up with the right words and stringing them into sentences — a condition called aphasia. Within hours of his stroke, Mr. Alter met with Loni Burke, a speech therapist who now works at Lenox Hill Hospital. At first he was completely nonverbal; within a few days he could say small words. “Mostly, he said, ‘No,’ ” Ms. Burke recalled, “because he was frustrated that he couldn’t speak.” Copyright 2008 The New York Times Company

Keyword: Language; Stroke
Link ID: 11548 - Posted: 06.24.2010

NEW YORK - Children should be screened for heart problems with an electrocardiogram before getting drugs like Ritalin to treat hyperactivity and attention-deficit disorder, the American Heart Association recommended Monday. Stimulant drugs can increase blood pressure and heart rate. For most children, that isn't a problem. But in those with heart conditions, it could make them more vulnerable to sudden cardiac arrest — an erratic heartbeat that causes the heart to stop pumping blood through the body — and other heart problems. About 2.5 million American children and 1.5 million adults take medication for attention-deficit hyperactivity disorder, or ADHD, according to government estimates. Stimulant drugs, like Ritalin, Adderall and Concerta, help children with ADHD to stay focused and control their behavior. The medications already carry warnings of possible heart risks in those with heart defects or other heart problems, which some critics said were driven more by concerns of overuse of the drugs than their safety. The heart group is now recommending a thorough exam, including a family history and an EKG, before children are put on the drugs to make sure that they don't have any undiagnosed heart issues. Copyright 2008 The Associated Press.

Keyword: ADHD
Link ID: 11547 - Posted: 06.24.2010

By CLAUDIA DREIFUS At Harvard, the social psychologist Daniel Gilbert is known as Professor Happiness. That is because the 50-year-old researcher directs a laboratory studying the nature of human happiness. Dr. Gilbert’s “Stumbling on Happiness” was a New York Times paperback best seller for 23 weeks and won the 2007 Royal Society Prize for Science Books. Q. HOW DID YOU STUMBLE ONTO YOUR AREA OF STUDY? A. It was something that happened to me roughly 13 years ago. I spent the first decade of my career studying what psychologists call “the fundamental attribution error,” which is about how people have the tendency to ignore the power of external situations to determine human behavior. Why do many people, for instance, believe the uneducated are stupid? I’d have been content to work on this for many more years, but some things happened in my own life. Within a short period of time, my mentor passed away, my mother died, my marriage fell apart and my teenage son developed problems in school. What I soon found was that as bad as my situation was, it wasn’t devastating. I went on. One day, I had lunch with a friend who was also going through difficult times. I told him: “If you’d have asked me a year ago how I’d deal with all this, I’d have predicted that I couldn’t get out of bed in the morning.” He nodded and added, “Are we the only people who could be so wrong in predicting how we’d respond to extreme stress?” That got me thinking. I wondered: How accurately do people predict their emotional reactions to future events? Copyright 2008 The New York Times Company

Keyword: Emotions
Link ID: 11546 - Posted: 06.24.2010

By HENRY FOUNTAIN Last week in this space, I referred to Joshua D. Wilson, an ocean engineering researcher, in one instance as “Dr. Johnson.” That was a mindless mistake if there ever was one. What was going on in my brain? A new study sheds some light on that question. The study — by Tom Eichele of the University of Bergen in Norway and collaborators including Vince D. Calhoun of the Mind Research Network in Albuquerque — used functional magnetic resonance imaging to look at what goes on in the brain before an error. Participants played a simple game that involved responding to arrows on a computer screen while the fMRI machine measured blood flow and oxygenation in parts of the brain. The idea, Dr. Eichele said, was to see if there were “brain activity patterns that would predict whether or not a response would be erroneous.” As he and his colleagues report in The Proceedings of the National Academy of Sciences, no single “blip” or event signals an error. Rather, brain patterns start to change about 30 seconds before an error is committed. “There are these linear gradients, gradual changes over time,” Dr. Eichele said. Copyright 2008 The New York Times Company

Keyword: Attention; Brain imaging
Link ID: 11545 - Posted: 06.24.2010

Patricia Hluchy How did a man declared brain dead by medical professionals end up back in the land of the living? The emergence of Zack Dunlap's story last month made some people wonder if it's possible to be written off prematurely in the trauma ward. Like a lot of young men in small towns, Zack lived for his wheels – a souped-up all-terrain vehicle. The 21-year-old factory worker spent his free time roaring around the countryside near his hometown, Frederick, Okla., a farming/ranching community of about 4,200. He was so adept at "wheelies" and stunts that his friends called him "Outlaw." Last November, he popped a wheelie that some insist was fatal – even though Zack is now walking and talking again. When he landed, he had to veer suddenly to avoid hitting a fellow ATVer, causing his four-wheeler to flip in the air. Zack, who wasn't wearing a helmet, crashed onto the pavement. Before long he was medevaced to United Regional Healthcare System in Wichita Falls, Tex., about 80 kilometres away, where he was put on a ventilator. Thirty-six hours after the accident, Zack was declared brain dead. The hospital notified the authorities, news reports of his death were published, and preparations were made to harvest his organs. © Copyright Toronto Star 1996-2008

Keyword: Miscellaneous
Link ID: 11544 - Posted: 06.24.2010

Biological, Emotional States Scrutinized By Rick Weiss Twenty years after DNA fingerprints were first admitted by American courts as a way to link suspects to crime scenes, a new and very different class of genetic test is approaching the bench. Rather than simply proving, for example, that the blood on a suspect's clothes does or does not match that of a murder victim, these "second generation" DNA tests seek to shed light on the biological traits and psychological states of the accused. In effect, they allow genes to "testify" in ways never before possible, in some cases resolving long-standing legal tangles but in others raising new ones. Already, chemical companies facing "toxic tort" claims have persuaded courts to order DNA tests on the people suing them, part of an attempt to show that the plaintiffs' own genes made them sick -- not the companies' products. In other cases, defense attorneys are asking judges to admit test results suggesting that their clients have a genetic predisposition for violent or impulsive behavior, adding a potential "DNA defense" to a legal system that until now has held virtually everyone accountable for their actions except the insane or mentally retarded. © 2008 The Washington Post Company

Keyword: Genes & Behavior; Emotions
Link ID: 11543 - Posted: 06.24.2010

Men and women in their early 40s with elevated blood cholesterol levels are more likely to develop Alzheimer's than those with low cholesterol, a report says. The new report is one of the largest studies to link cholesterol to the degenerative brain disease. Alina Solomon of the University of Kuopio in Finland, Rachel Whitmer of the Kaiser Permanente Division of Research in Oakland and their colleagues obtained cholesterol values for 9,752 men and women who were in their 40s from 1964 through 1973. The team found that 504 had developed Alzheimer's by 2007. This study, and other evidence, suggests the disease is influenced by factors that can be changed. Solomon says people can reduce high blood cholesterol with a diet low in saturated fat. Heavy smokers and drinkers develop Alzheimer's years before people who don't drink or smoke as much, a new report says. The study, presented Wednesday at the American Academy of Neurology meeting in Chicago, suggests heavy drinking and smoking might be accelerating damage to the brain, which could lead to Alzheimer's. But the flip side of the study is a message of hope: People who cut back or stop habits such as excessive smoking or drinking might reduce their risk of developing Alzheimer's at a younger age. Instead of struggling with forgetfulness at age 59, such people might delay symptoms until age 65 or 70, says researcher Ranjan Duara of the Mount Sinai Medical Center in Miami Beach. Copyright 2008 USA TODAY,

Keyword: Alzheimers; Drug Abuse
Link ID: 11542 - Posted: 04.22.2008

Commonly used incontinence drugs may cause memory problems in some older people, a study suggests. "Our message is to be careful when using these medicines," said U.S. navy neurologist Dr. Jack Tsao, who led the study. "It may be better to use diapers and be able to think clearly than the other way around." Urinary incontinence sometimes can be resolved with non-drug treatments, he added, so patients should ask about alternatives. Exercises, biofeedback and keeping to a schedule of bathroom breaks work for many. U.S. sales of prescription drugs to treat urinary problems topped $3 billion US in 2007, according to IMS Health, which tracks drug sales. Bladder control trouble affects about one in 10 people age 65 and older, according to the National Institute on Aging, which helped fund the study. Women are more likely to be affected than men. Causes include nerve damage, loss of muscle tone or, in men, enlarged prostate. © The Canadian Press, 2008

Keyword: Learning & Memory
Link ID: 11541 - Posted: 06.24.2010

By Rebecca Morelle Scientists have been able to take control of flies' brains to make females behave just like males. Researchers genetically modified the insects so that a group of brain cells that control sexual behaviour could be "switched on" by a pulse of light. The team was able to get female fruit flies to produce a courtship song - behaviour usually only seen in males. The study, published in the journal Cell, suggests that the wiring in male and female flies' brains is similar. Gero Miesenboeck, from Oxford University, UK, who carried out the research with J. Dylan Clyne from Yale University, US, said: "It is often the case that males have to work very hard to convince females to mate with them. In many animal species, males have to put on elaborate courtship displays to impress females - even the tiny fruit fly." Male fruit flies will vibrate one of their wings to produce a barely audible song, explained Professor Miesenboeck. "And if the female likes that sound, she'll surrender to his advances." Previous research has revealed that a group of 2,000 brain cells are necessary for this courtship behaviour in the insects; however, both male and female fruit flies appear to possess most of these neurons. BBC © MMVII

Keyword: Sexual Behavior; Genes & Behavior
Link ID: 11540 - Posted: 06.24.2010

Patricia Yollin, Chronicle Staff Writer Octopus sex is simple, dull and quick - at least that's what scientists used to think. Instead, it turns out to be complex, sophisticated and rife with petty rivalries. In the most detailed research ever conducted on this topic in the wild, UC Berkeley biologists focused on the mating behavior of the Abdopus aculeatus, one of more than 300 species of octopus. They were stunned at what they learned. "The main surprise was the fact we had this idea that they were completely solitary, with interactions few and far between," said Christine Huffard, lead author on a study recently published in Marine Biology, a science journal. "But they interacted so much more than we ever expected." She discovered that the males were very picky and discriminating, that the females would have sex with just about anybody, and that male competition for females tended to be violent and frequent. "Christine actually followed the aculeatus from dawn to dusk," said Roy Caldwell, a co-author of the study and professor of integrative biology at UC Berkeley. "Nobody had done that kind of intensive field work on any octopus." Huffard, who received her Ph.D. in biology from Cal, came across the species while she was living in Sulawesi, Indonesia, helping a friend with research. "I happened to find them," she recalled. "It was completely serendipitous." Caldwell said, "We went snorkeling and suddenly realized there were octopus everywhere." © 2008 Hearst Communications Inc

Keyword: Sexual Behavior
Link ID: 11539 - Posted: 06.24.2010